Point Loma  Mixed in with the bursting slate of theater, dance and visual art performances at this weekend's Without Walls Festival at La Jolla Playhouse, it was surprising that there was only one ticketed music installation.

Presented Friday and Saturday at the Wegman Overlook, a serene tree-lined cliff with a panoramic view of La Jolla, the 45-minute work for flute, voice and percussion celebrated both the beauty of nature and its hypnotic rhythms.

Sciarrino wrote the 1985 piece for outdoor performance, and if you closed your eyes, it was often hard to tell which sounds are human-produced and which are created by Mother Nature.

Flutist Rachel Beetz opened the modern, minimalist piece creating not traditional music but haunting whispers and blasts of sound on her instrument that resemble the whistle of wind through the creaky hinges of a rusty gate, distant ship horns, wind chimes and even the roar of prehistoric animals.

As the piece climaxes, the music transitions from nature's rhythms to space age/sci-fi sounds. Sciarrino intended this section of the piece to be dramatized with flying kites laden with bells. Wind and space restrictions made this impossible at Wegman, but Jennifer Bewerse created three Mylar balloon bouquets that popped up behind the musicians and soared lazily in the sky. The effect was interesting but didn't have the visual impact it could have because the balloons were too far away from the stage.